Mii

Nintendo Wii has the possibility to define characters that represent you in the games. You have the possibility to change these characters. To do that you need the one or the other Mii editor.

If you just want to cut to the chase and download a whole bunch of Mii’s you can do that here.
There are several possibilities which can be used. Of course you can do it using the Wii which is the traditional way but there are other options.
First there is the My Avitar Editor. This is a swf file which can be run in execution mode on your PC. You get the screen below where you can edit, change and even save to picture file on your PC.
On these links you can do this online. http://www.codejunkies.com/miieditor/ and http://www.miisearch.com/mii-creator.html
The second option is to use a dedicted program which configues your file in the same way. (The middle picture is the Wii Mii editor v1.2)
The files that are produced are mae (Mii avitar editor) files or mii files but both are identical. Once you have generated these files you can upload them to this site http://www.miicharacters.com/wii.php?mii=188 and get the helpfull instructonal that is pictured on the right. If you want to generate a Mii from the instruction set you have to start with the default characters. These are defaultBoy.mae and defaultGrl.mae.
There is also the possibility to make a special Mii. You can read about it here. http://www.davidhawley.co.uk/special-miis-gold-pants-and-creating.aspx
What i normally do is generate a set of Wii instruction as the picture below. These i then enter them manually into the Wii.
I find this the easiest way to make Mii’s and get them into the Wii.

The Mii data is stored on the Wiimote in two blocks. Each block is composed of 750 bytes of Mii data, followed by a 2 byte CRC. If the data in the first block does not match the CRC for that block, the second block is used instead. At that point, if the CRC of the second block does not match its data, no Mii data will be available.
The blocks are 752 bytes in length (0x2f0 bytes), and are stored consecutively starting at address 0x0fca in the Wiimote memory.

At the beginning of each block, there is a 4-byte value (‘RNCD’) which may be a Mii software version number, as it is the same across multiple Wiis and multiple Wiimotes. After these 4 bytes, there are 2 bytes which determine which slots are Mii parade slots. Left shift 0x0001 by the slot number to set it as Mii parade (hidden when viewed on the Wiimote). If a slot is empty, or filled by a non-parade Mii, its parade slot bit will be set to 0.
The last two bytes of the block are a CRC-16 CCITT of the previous 750 bytes (polynomial 0x1021, starting value 0x0000).
This is a short (but working) version of the CRC calculation algorithm, written in Java (should be easy to adapt for arduino IDE).
You could using a SD shield adapt such a block dataset and upload it directly into the wii. There are a number of programs that can do that. You can find them here http://wiibrew.org/wiki.